M13 is visible to the unaided eye on the side of the "keystone" shape in Hercules.

Astro-Physics 155 mm refractor at f7. 19 3-minute exposures at ASA 800 using a Canon 40D from 9:48 p.m. to 11:17 p.m. EDT on 2008-08-31 from Northern New Jersey. ©2008